// Copyright 2018 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

// +build amd64

// Package atomicbitops provides basic bitwise operations in an atomic way.
// The implementation on amd64 leverages the LOCK prefix directly instead of
// relying on the generic cas primitives.
//
// WARNING: the bitwise ops provided in this package doesn't imply any memory
// ordering. Using them to construct locks must employ proper memory barriers.
package atomicbitops

// AndUint32 atomically applies bitwise and operation to *addr with val.
func AndUint32(addr *uint32, val uint32)

// OrUint32 atomically applies bitwise or operation to *addr with val.
func OrUint32(addr *uint32, val uint32)

// XorUint32 atomically applies bitwise xor operation to *addr with val.
func XorUint32(addr *uint32, val uint32)

// CompareAndSwapUint32 is like sync/atomic.CompareAndSwapUint32, but returns
// the value previously stored at addr.
func CompareAndSwapUint32(addr *uint32, old, new uint32) uint32

// AndUint64 atomically applies bitwise and operation to *addr with val.
func AndUint64(addr *uint64, val uint64)

// OrUint64 atomically applies bitwise or operation to *addr with val.
func OrUint64(addr *uint64, val uint64)

// XorUint64 atomically applies bitwise xor operation to *addr with val.
func XorUint64(addr *uint64, val uint64)

// CompareAndSwapUint64 is like sync/atomic.CompareAndSwapUint64, but returns
// the value previously stored at addr.
func CompareAndSwapUint64(addr *uint64, old, new uint64) uint64

// IncUnlessZeroInt32 increments the value stored at the given address and
// returns true; unless the value stored in the pointer is zero, in which case
// it is left unmodified and false is returned.
func IncUnlessZeroInt32(addr *int32) bool

// DecUnlessOneInt32 decrements the value stored at the given address and
// returns true; unless the value stored in the pointer is 1, in which case it
// is left unmodified and false is returned.
func DecUnlessOneInt32(addr *int32) bool
